21 research outputs found
The Far-Ultraviolet "Continuum" in Protoplanetary Disk Systems II: CO Fourth Positive Emission and Absorption
We exploit the high sensitivity and moderate spectral resolution of the
-Cosmic Origins Spectrograph to detect far-ultraviolet spectral features
of carbon monoxide (CO) present in the inner regions of protoplanetary disks
for the first time. We present spectra of the classical T Tauri stars HN Tau,
RECX-11, and V4046 Sgr, representative of a range of CO radiative processes. HN
Tau shows CO bands in absorption against the accretion continuum. We measure a
CO column density and rotational excitation temperature of N(CO) = 2 +/- 1
10 cm and T_rot(CO) 500 +/- 200 K for the absorbing gas.
We also detect CO A-X band emission in RECX-11 and V4046 Sgr, excited by
ultraviolet line photons, predominantly HI LyA. All three objects show emission
from CO bands at 1560 \AA, which may be excited by a combination
of UV photons and collisions with non-thermal electrons. In previous
observations these emission processes were not accounted for due to blending
with emission from the accretion shock, collisionally excited H, and
photo-excited H2; all of which appeared as a "continuum" whose components could
not be separated. The CO emission spectrum is strongly dependent upon the shape
of the incident stellar LyA emission profile. We find CO parameters in the
range: N(CO) 10 cm, T_{rot}(CO) > 300 K for the LyA-pumped
emission. We combine these results with recent work on photo- and
collisionally-excited H emission, concluding that the observations of
ultraviolet-emitting CO and H2 are consistent with a common spatial origin. We
suggest that the CO/H2 ratio in the inner disk is ~1, a transition between the
much lower interstellar value and the higher value observed in solar system
comets today, a result that will require future observational and theoretical
study to confirm.Comment: 12 pages, 7 figures, 3 tables. ApJ - accepte
A Far-ultraviolet Atlas of Low-resolution Hubble Space Telescope Spectra of T Tauri Stars
We present a far-ultraviolet (FUV) spectral atlas consisting of spectra of 91
pre-main sequence stars. Most stars in this sample were observed with the Space
Telescope Imaging Spectrograph (STIS) and Advanced Camera for Surveys (ACS) on
the \emph{Hubble Space Telescope} (\emph{HST}). We find strong correlations
among the \ion{O}{1} 1304 triplet, %\ion{C}{2} 1335, the
\ion{Si}{4} 1394/1403 doublet, the \ion{C}{4} 1549
doublet, and the \ion{He}{2} 1640 line luminosities. For classical T
Tauri stars (CTTSs), we also find strong correlations between these lines and
the accretion luminosity, suggesting that these lines form in processes related
to accretion. These FUV line fluxes and X-ray luminosity correlate loosely with
large scatters. The FUV emission also correlates well with H, H,
and \ion{Ca}{2} K line luminosities. These correlations between FUV and optical
diagostics can be used to obtain rough estimates of FUV line fluxes from
optical observations. Molecular hydrogen (H) emission is generally
present in the spectra of actively accreting CTTSs but not the weak-lined T
Tauri stars (WTTSs) that are not accreting. The presence of H emission in
the spectrum of HD 98800 N suggests that the disk should be classified as
actively accreting rather than a debris disk. The spectra in the atlas are
available at http://archive.stsci.edu/prepds/ttauriatlas.Comment: 89 pages, 30 figures, published in Ap
Modelling human choices: MADeM and decision‑making
Research supported by FAPESP 2015/50122-0 and DFG-GRTK 1740/2. RP and AR are also part of the Research, Innovation and Dissemination Center for Neuromathematics FAPESP grant (2013/07699-0). RP is supported by a FAPESP scholarship (2013/25667-8). ACR is partially supported by a CNPq fellowship (grant 306251/2014-0)
How Religion, Social Class, and Race Intersect in the Shaping of Young Women’s Understandings of Sex, Reproduction, and Contraception
Using a complex religion framework, this study examines how and why three dimensions of religiosity—biblical literalism, personal religiosity, and religious service attendance—are related to young women’s reproductive and contraceptive knowledge differently by social class and race. We triangulate the analysis of survey data from the Relationship Dynamics and Social Life (RDSL) study and semi-structured interview data from the National Study of Youth and Religion (NSYR) to identify and explain patterns. From the quantitative data, we find that all three dimensions of religiosity link to young women’s understandings of sex, reproduction, and contraception in unique ways according to parental education and racial identity. There is a lack of knowledge about female reproductive biology for young women of higher SES with conservative Christian beliefs (regardless of race), but personal religiosity and religious service attendance are related to more accurate contraceptive knowledge for young black women and less accurate knowledge for young White women. From the qualitative data, we find that class and race differences in the meaning of religion and how it informs sexual behavior help explain results from the quantitative data. Our results demonstrate the importance of taking a complex religion approach to studying religion and sex-related outcomes
How Religion, Social Class, and Race Intersect in the Shaping of Young Women’s Understandings of Sex, Reproduction, and Contraception
Using a complex religion framework, this study examines how and why three dimensions of religiosity—biblical literalism, personal religiosity, and religious service attendance—are related to young women’s reproductive and contraceptive knowledge differently by social class and race. We triangulate the analysis of survey data from the Relationship Dynamics and Social Life (RDSL) study and semi-structured interview data from the National Study of Youth and Religion (NSYR) to identify and explain patterns. From the quantitative data, we find that all three dimensions of religiosity link to young women’s understandings of sex, reproduction, and contraception in unique ways according to parental education and racial identity. There is a lack of knowledge about female reproductive biology for young women of higher SES with conservative Christian beliefs (regardless of race), but personal religiosity and religious service attendance are related to more accurate contraceptive knowledge for young black women and less accurate knowledge for young White women. From the qualitative data, we find that class and race differences in the meaning of religion and how it informs sexual behavior help explain results from the quantitative data. Our results demonstrate the importance of taking a complex religion approach to studying religion and sex-related outcomes.https://digitalcommons.snc.edu/faculty_staff_works/1038/thumbnail.jp
A Comparison of Single Sample and Bootstrap Methods to Assess Mediation in Cluster Randomized Trials
Hypothalamic-Pituitary Disorders in Childhood Cancer Survivors : Prevalence, Risk Factors and Long-Term Health Outcomes
CONTEXT: Data on hypothalamic-pituitary (HP) disorders in systematically evaluated childhood cancer survivors are limited. OBJECTIVE: To describe prevalence, risk factors, and associated adverse health outcomes of deficiencies in GH deficiency (GHD), TSH deficiency (TSHD), LH/FSH deficiency (LH/FSHD), and ACTH deficiency (ACTHD), and central precocious puberty (CPP). DESIGN: Retrospective with cross-sectional health outcomes analysis. SETTING: Established cohort; tertiary care center. PATIENTS: Participants (N = 3141; median age, 31.7 years) were followed for a median 24.1 years. MAIN OUTCOME MEASURE: Multivariable logistic regression was used to calculate ORs and 95% CIs for associations among HP disorders, tumor- and treatment-related risk factors, and health outcomes. RESULTS: The estimated prevalence was 40.2% for GHD, 11.1% for TSHD, 10.6% for LH/FSHD, 3.2% for ACTHD, and 0.9% for CPP among participants treated with HP radiotherapy (n = 1089), and 6.2% for GHD, and 30 Gy for ACTHD), alkylating agents (GHD, LH/FSHD), intrathecal chemotherapy (GHD), hydrocephalus with shunt placement (GHD, LH/FSHD), seizures (TSHD, ACTHD), and stroke (GHD, TSHD, LH/FSHD, ACTHD). Adverse health outcomes independently associated with HP disorders included short stature (GHD, TSHD), severe bone mineral density deficit (GHD, LH/FSHD), obesity (LH/FSHD), frailty (GHD), impaired physical health-related quality of life (TSHD), sexual dysfunction (LH/FSHD), impaired memory, and processing speed (GHD, TSHD). CONCLUSION: HP radiotherapy, central nervous system injury, and, to a lesser extent, chemotherapy are associated with HP disorders, which are associated with adverse health outcomes